Plantinga appears to have been wrong: the crucial premise of his modal ontological argument -- viz., that a maximally great being (as Plantinga understands that notion) is metaphysically possible -- is contrary to reason. For the notion of a being that is the creator of all other concrete objects distinct from himself is on a par with the concept of the creator and sustainer of round squares, as both entail a metaphysical impossibility.

Here's a rough draft of yet another argument I'm toying with that's in the same vein as several others I've discussed here recently:

Suppose for reductio that it's metaphysically possible that a necessary being exists, and that this being is the god of classical Anselmian theism. Let's follow Plantinga's claim here that such a being has the property of maximal greatness, where: (i) a being's maximal greatness entails maximal excellence in every possible world, (ii) maximal excellence includes the classical attributes of omniscience, omnipotence, and moral perfection, and (iii) omnipotence includes the capacity to create or sustain concrete objects distinct from itself without a material cause. Therefore, if it's metaphysically possible that a maximally great being exists, then such a being exists in all metaphysically possible worlds. Therefore, a maximally great being exists in all metaphysically possible worlds. By the above conception of maximal excellence, for any world W that contains a universe of concrete objects distinct from God, if God exists in W, then God originates or sustains the universe in W without a material cause. But the origination or sustenance of any such universe without a material cause is metaphysically impossible. Now a universe of concrete objects exists at the actual world. Therefore, the god of classical Anselmian theism did not originate or sustain the universe that exists at the actual world. Therefore, the god of classical Anselmian theism doesn't exist at the actual world. But this contradicts the above line that he exists in all possible worlds. Therefore, the existence of the god of classical Anselmian theism is metaphysically impossible.

The upshot is that Plantinga appears to have been wrong: the crucial premise of the modal ontological argument -- viz., that a maximally great being (as Plantinga understands that notion) is metaphysically possible -- is contrary to reason. For we've just seen that the notion of a being that is the creator of all other concrete objects distinct from himself is on a par with the concept of a being that is the creator of round squares, as both entail a metaphysical impossibility.

In the last post I noted the 3AM interview with Gregory Dawes. Here I want to highlight a portion of the interview that I'd like to discuss. It's the point where Richard Marshall brings up the recent hot topic of bias in philosophy of religion, pointing to Chalmers' PhilSurveys results. Here is Marshall's question, followed by Dawes' response:

3:AM: David Chalmers has done a survey that suggests that although most philosophers are atheists most philosophers of religion are not. Why do you think that philosophers generally don’t seem to be bothered that the sub group specializing in philosophizing about religion are disagreeing with them? It’s a strange situation isn’t it, that a sub group of experts are disregarded by the rest of the field.

GD: Yes, but it’s an interesting fact, and it tells us something about the nature of religious faith and its relation to reason.

Christian philosopher William Lane Craig writes somewhere about what he calls the “ministerial” and the “magisterial” use of reason. (It’s a traditional view — he’s merely citing Martin Luther — and one that Craig endorses.) On this view, the task of reason is to find arguments in support of the faith and to counter any arguments against it. Reason is not, however, the basis of the Christian’s faith. The basis of the Christian’s faith is (what she takes to be) the “internal testimony of the Holy Spirit” in her heart. Nor can rational reflection can be permitted to undermine that faith. The commitment of faith is irrevocable; to fall away from it is sinful, indeed the greatest of sins.

It follows that while the arguments put forward by many Christian philosophers are serious arguments, there is something less than serious about the spirit in which they are being offered. There is a direction in which those arguments will not be permitted to go. Arguments that support the faith will be seriously entertained; those that apparently undermine the faith must be countered, at any cost. Philosophy, to use the traditional phrase, is merely a “handmaid” of theology.

There is, to my mind, something frivolous about a philosophy of this sort. My feeling is that if we do philosophy, it ought to be because we take arguments seriously. This means following them wherever they lead. This may sound naïve. There are moral commitments, for instance, that few of us would be prepared to abandon, even if we lacked good arguments in their support. But if the followers of Hume are right, there is a close connection between our moral beliefs and our moral sentiments that would justify this attitude. In any case, even in matters of morality, we should not be maintaining positions that have lots of arguments against them and few in their favour, just because we have made a commitment to do so.

So why does the philosophy of religion have such a marginal status within the philosophical community? It may be (as some Christians assert) because atheist philosophers “love darkness more than light,” but I suspect it’s because many atheist philosophers not only find the arguments unconvincing but also regard this style of philosophy as distasteful.

Now as a matter of fact, Dawes doesn't get Craig's official view about the internal testimony of the Holy Spirit quite right, but I do have serious worries that something troublingly similar to his diagnosis might be correct. I also suspect that Dawes here captures the essence of why many philosophers who don't have an AOS in philosophy of religion steer clear of it. Thoughts?

Here's another argument I'm toying with that's in the same vein as several others I've discussed here previously:

Suppose some natural order (e.g., teleology in organic and non-organic structures, fine-tuning, irreducibly complex biochemical structures, etc.) is best explained in terms of intelligent design. Now if the designer is the God of classical theism, then God ultimately produced the objects of design ex nihilo, without preexisting things or stuff. But all finite concrete objects are ultimately produced from preexisting things or stuff. Therefore, some natural order is best explained in terms of intelligent design only if classical theism is false.

Evolutionary debunking arguments (EDAs) against religious beliefs move from the claim that religious beliefs are caused by off-track processes to the conclusion that said religious beliefs are unjustified and/or false. Prima facie, EDAs commit the genetic fallacy, unduly conflating the context of discovery and the context of justification. In this paper, we first consider whether EDAs necessarily commit the genetic fallacy, and if not, whether modified EDAs (e.g., those that posit falsehood-tracking or perniciously deceptive belief-forming mechanisms) provide successful arguments against theism. Then, we critically evaluate more recent attempts to argue that a more promiscuous evolutionary scepticism renders religious belief unjustified because, unlike commonsense and scientific beliefs, religious beliefs have no way out of such scepticism.

It's final's time, and I'm buried in work. So in lieu of a new post, here's an old comment of mine pulled from the archives:

Plantinga
follows Roderick Chisholm in his rejection of epistemological methodism, on the
grounds that always requiring criteria for how one knows something leads to a
vicious infinite regress, and thus to skepticism. He also follows Chisholm in
adopting a particularlist, inductive method of generating criteria of proper
basicality. As Plantinga puts it:

"We
must assemble examples of beliefs and conditions such that the former are
obviously properly basic in the latter, and examples of beliefs and conditions
such that the former are obviously not properly basic in the latter. We must
then frame hypotheses as to the necessary and sufficient conditions of proper
basicality and test these hypotheses by reference to those examples."
(Plantinga, Alvin. "Reason and Belief in God", in Faith and
Rationality: Reason and Belief in God (U of Notre Dame Press, 1983), p. 76.).

So
the idea is that clear cases of particular instances of knowledge are
epistemically prior to general criteria for knowledge. From the particular
cases, one examines what features they have in common, and then formulates
hypotheses to the effect that all beliefs with those features are tokens of
knowledge.

I think Plantinga goes wrong by liberalizing and relativizing
Chisholmian particularism. Plantinga intends his use of "obviously"
in the passage above to be relativized to epistemic communities ("obvious
to us folks"), so as to allow controversial beliefs that are nonetheless
strongly held in a given epistemic community to qualify as "obvious",
and thereby to allow for correspondingly relativized, theism-friendly criteria
of proper basicality. This goes against the spirit of Chisholm's approach, as
his intent was to only countenance Moorean facts as clear cases of knowledge.

Ironically,
Chisholm warns against the dangers of a liberalized standard of clear cases of
knowledge in The Problem of the Criterion, the very book Plantinga
appeals to as the basis of his fundamental epistemological approach: “We are
all acquainted with people who think they know a lot more than in fact they do
know. I’m thinking of fanatics, bigots, mystics, and various types of
dogmatists.”

Alvin Plantinga notes that if what Christians believe is true, their beliefs are warranted. It follows, he argues, that the only decisive objection to Christian belief is a de facto one: an argument that shows that what Christians believe is false. We disagree. A critic could mount a direct attack on the Christian’s claim to warrant by offering a more plausible account of the causal mechanism giving rise to belief, one that shows that mechanism to be unreliable. This would represent a powerful de jure argument against Christian belief.

(Draft. Revised in light of Chris' and Jeffery's comments. Further revisions and developments -- esp. fleshing out support for the premises -- to come.)
So here's a sketch of another argument in the same vein as severalothersI'veblogged about recently:

The basic idea is that classical theism entails that if there are any created minds, then at least one such mind was created without prior materials. Now if substance dualism is true, then minds are concrete objects. But no concrete object can be created without prior things or stuff(s). Therefore, if substance dualism is true, then classical theism is false.
To make the reasoning more concrete, let's just focus on one mind -- one from the actual world. In particular, let 'Adam's mind' denote the first finite, human mind to come into existence. Then we can put the reasoning in standard form as follows:

1. If substance dualism is true, then all finite minds are finite
concrete objects.